Dealing with Increased Incidence of Tuberculosis Cases

Mr Melvin Yong Yik Chye asked the Minister for Health in view of the continued increase in the number of active TB cases from 2017 to 2018 (a) what measures are in place for early TB detection; and (b) whether the current measures to contain local TB cases are effective.

The incidence rates of active tuberculosis (TB) cases in 2017 and 2018 were similar, at 39 cases per 100,000 resident population. In fact, the rate had remained within a stable range of about 37 to 41 cases per 100,000 over the last five years.

In 2018, almost half of new active TB cases were aged 60 years old and older, although their incident rates had also remained stable. Many older Singaporeans were exposed to TB when they were younger, when incidence rates in Singapore were much higher. As such, up to 30% have latent TB. Latent TB patients do not exhibit symptoms and are not infectious, but one in 10 may progress to active TB during their lifetime.

The World Health Organization (WHO) and local experts do not recommend population-level preventive medication to treat latent TB. Those with active TB and recent latent TB infection will be treated with medication. The treatment approach for older Singaporeans is the same as for the general population.

To contain TB transmission, the Tuberculosis Control Unit (TBCU) conducts contact investigations to identify persons who have had close and prolonged contact with infectious TB cases. Contacts are tested for TB for early detection and treatment of the disease to prevent its spread.

MOH launched the TB Clinical Practice Guidelines in 2016 to strengthen TB management.

For Multi-Drug Resistant TB (MDR-TB), patients are isolated for treatment until they become non-infectious, which takes about two months, and they will undergo directly observed therapy (DOT) for about two years. We have also adopted new technologies such as rapid DNA tests for drug resistance, reducing time taken for identification of MDR-TB from two months to a few hours to facilitate early intervention.

I thank the Senior Parliamentary Secretary. I have two supplementary questions. First, will the Ministry consider setting a public target to be achieved for TB control? Second, what are other plans that MOH has in improving public education and awareness of TB, especially among our elderly?

Due to the previous exposure when TB rates were quite high in the 1950s and 1960s, there is now a fairly significant number of older Singaporeans with latent TB infection. Waning immunity in older adults also contributes to reactivation of latent TB later on in life. Hence, it is quite difficult to set a firm target to achieve firm TB control. But in the longer term, our goal is to benchmark ourselves against high-income countries that have TB rates of about less than 20 cases per 100,000 population.

As for the strategy, we adopt a three-pronged strategy towards reducing TB incidence rates.

The first strategy is to improve public knowledge of TB. Besides information on MOH's webpages and press releases, HPB also runs campaigns, specifically, a social hygiene campaign called "Fight Each Year" and this is aimed at promoting good hygiene practices and help prevent the spread of infectious diseases. Exhibitions are conducted at Tan Tock Seng Hospital on annual World TB Day to educate the public.

The second strategy is to educate healthcare practitioners about current practices in their diagnosis and management of TB. Towards this end, the Clinical Practice Guidelines were launched in 2016 and these contain information on TB diagnostic tools, treatment regimes and public health measures for TB control.

And finally, MOH is also reviewing its policies and measures to increase early detection of active TB.

I thank the Senior Parliamentary Secretary for the answer. I have a couple of follow-up questions. First, based on the case data, does MOH know, especially for the new cases, at what stage do they seek medical consultation? Is it early on or is it later? Because that follows up with my next question. Are MOH's current public awareness, current measures to contain local cases effective?

Of the 1,565 new cases reported last year, that is, 2018, more than two-third, or about 1,130, were at least 50 years old. More than half of these were males. So, I am not sure whether some of the efforts can more targeted to focus on these vulnerable and higher risk groups.

My last question is, with an ageing population and based on what the Senior Parliamentary Secretary just said, would MOH expect the incidence rate to continue to increase? Due to our ageing population?

I do not have the information on the stage in which the TB cases are detected. On the second question on what will be done, we are constantly looking at ways to improve and as for extensive, it depends on the effectiveness of the strategy that we have implemented. As I mentioned just now, we have the three-pronged strategy. If we stick to that strategy and everyone cooperates, I think we stand a better chance at controlling transmission.

Mr Speaker, may I ask the Senior Parliamentary Secretary how big is the problem of drug-resistant TB in Singapore? Have we done any studies on that? And whether MOH is using any new drug cocktail to overcome this problem.